Adjustable Multistage Pressure Reducing Regulator

ABSTRACT

A multi-stage pressure regulation system, device and associated methodology for reducing the pressure of gas passing through a gas sample conditioning system. The device and method allow for automatic and/or manual configuration settings for regulating different types of gas having different profiles while still avoiding dew point dropout thereby ensuring accurate sample analysis at a downstream analyzer. The pressure regulating device includes a housing having a core, a vapor sample input port, a plurality of openings on an upper surface, a plurality of pressure regulating valves configured to reduce the pressure of a vapor sample, and an assembly having a base and substantially central stem orthogonal to the base and extending axially therefrom, the stem being disposed within the core.

FIELD OF THE INVENTION

This invention relates to a vapor pressure reduction method andadjustable/calibratable multistage pressure reducing regulating device.The invention allows for intelligent automatic or manual adjustabilityadapted for customization according to particular thermodynamicrequirements of the stepped depressurization of a condensable vapor gasas dictated by phase curves associated with the particular properties ofthe vapor gas. The invention when employed in a vaporized natural gassample conditioning application provides a compact system and method forcontrolled staged pressure reduction of a vapor gas sample that avoidsJoule-Thomson/dew point dropout condensation while maintaining thecompositional integrity of the vapor throughout the depressurizationprocess to provide a vapor sample at a low enough pressures to benon-damaging to a downstream analyzer.

BACKGROUND OF THE INVENTION

Although described herein in the context of natural gas, for which theinvention is very useful, the invention is not intended to be limitedexclusively to application in the natural gas sampling field. Due to itscharacteristics as a combustible, gaseous mixture of multiplehydrocarbon compounds the precise composition of which can vary widelyparticularly when produced by fracking, Natural Gas Liquids (NGL)possesses a broad array of characteristics. For example, a particularliquid can be composed of ethane, propane, butane, isobutane, pentanes,etc. and, therefore, can be useful for various applications such as,heating, fuel, and upon separation/fractionation, petrochemicalfeedstock, plastics manufacturing, etc. The last decade has seensignificant advancements in technologies such as horizontal drilling andhydraulic fracturing techniques which have led to a steady increase inNGL production.

In contrast to NGL, high methane content Liquid Natural Gas (LNG) isproduced by taking natural gas from a production field, removingimpurities, and liquefying the natural gas for transfer. LNG is saferand easier to transport in the gas/vapor phase as it takes upapproximately 1/600^(th) the volume of natural gas in the vapor state.Natural gas is mainly converted to LNG for long distance domestictransport or transport overseas by ship where laying pipelines is noteconomically or technically feasible.

When employed as an energy source, the energy content of natural gas,LNG and NGLs are typically measured and reported in BTUs. In the processof custody transfer and end use of NGL and LNG products, it is importantthat the BTU measurement of any particular extracted gas sample beaccurate. Accordingly, in the context of custody transfer, accuratesampling and analysis of samples along various points in thedistribution network, from the source, through a pipeline network to theend user, has economic importance. Particularly when the liquid naturalgas supply results from input originating with different sources andlocations, accountability of the varying energy content at any givenpoint in the pipeline has financial consequences. Therefore,particularly in custody transfer operations, from an energy auditingperspective the respective energy content values of a liquid feedstockat each stage must be accurately and precisely sampled.

Further, some samples, such as an extracted natural gas sample, may becontaminated with small amounts of impurities that require detection andremoval. Sour gas can comprise trace contaminants such as, mercury (Hg),hydrogen sulfide (H₂S), carbonyl sulfide (COS), mercaptans (R-SH), andaromatic compounds including those from the group known as BTEX(Benzene, Toluene, Ethylbenzene and Xylene). Accordingly, the amount ofthese trace contaminants must be accurately and precisely sampled todetermine the quality of the sample.

Gas sample conditioning systems provide the capability for such accurateand precise sampling. One preferred system for sampling natural gasincludes the Mustang® P53® Sample Conditioning System available fromMustang Sampling, LLC of Ravenswood, W. Va. and described in U.S. Pat.No. 7,162,933, the entirety of which is herein incorporated byreference. When sampling LNG and more significantly, NGL, an importantpart of the gas sample conditioning process relates to vaporization of aliquid sample extracted via a probe from a gas pipeline or source andmaintaining the compositional integrity of that vaporized sample fromtakeoff to analysis. To that end, the Applicant of the present inventionhas introduced several systems and techniques directed to generating andmaintaining accurate and precise NGL and LNG extracted sampleconditioning and control, such as those described and disclosed inpatents USRE47478, U.S. Pat. No. 9,285,299, U.S. Pat. No. 10,281,368,U.S. Pat. No. 7,484,404, and U.S. Pat. No. 9,057,668, the entirety ofeach which is herein incorporated by reference, and sold as Mustang®Vaporizer Sampling Systems. Specifically, to vaporize the extractedliquid sample, the Mustang Vaporizer Sampling System® and Mustang® NGLSample Conditioning System can include a vaporizer device whichvaporizes an incoming sample as it cascades around an internal heatingcore. An exemplary vaporizer device for such purposes is described inApplicant's U.S. Pat. No. 10,613,006 (WO2020068325A1), the entirety ofwhich is herein incorporated by reference.

Once an incoming liquid sample is vaporized into a gaseous state, thegas vapor is passed through small diameter tubing composed of acorrosion-resistant super alloy or equivalent to an analyzer, such as achromatograph. A person of ordinary skill readily appreciates that a gaschromatograph analyzes a gas/vapor sample, identifies and quantifies theconstituent gas/vapor components, and provides a data outputrepresentative of the extracted sample's energy content.

To accurately analyze a gas sample derived from a liquid source withoutdamaging an analyzer/chromatograph, a gas sample exiting a vaporizertypically at a high pressure must be depressurized (by up to twomagnitudes) to an analyzer safe level before introduction. By way ofexample, a vaporized NGL sample may exit the vaporizer at a highpressure, greater than 6996.11 kPa which must then be reduced to ananalyzer safe pressure, typically between 135.83 kPa −328.88 kPa toavoid damaging and/or rendering the analyzer inoperative. However, atany specific pressure, if the temperature of a gas sample, whether aheterogeneous mixture of components possessing a range of vaporcondensation lines or a substantially homogeneous composition with amore predictable phase envelope curve, decreases so as to intersect aparticular liquid-vapor phase curve, dew point condensation/hydrocarbondew point dropout results. In such an event and as a result of thegas/vapor thermodynamic properties, the vapor gas sample reverts intoliquid form. This undesirable phase transition not only diminishesaccuracy of energy content evaluation but also compromises thedownstream analyzer/chromatograph, due to liquid input generated fromthe gas sample transiting through the condensation/phase transitionboundary. By way of example, in the natural gas field, failure toadequately maintain pressure and temperature parameters of a vaporizedsample will cause Joule-Thomson hydrocarbon dew point dropout.Introduction of such liquid invariably damages the chromatographicpacking by column bleed which, in turn, results in generation of falsereadings from ghost peaks, etc. Such fouling may require taking thepoisoned unit off-line either for complete replacement or forrestoration to an operationally acceptable condition which In the caseof a large scale transfer operation, causes major disruptions to normalprocessing.

Accordingly, to obtain accurate and precise natural gas constituentanalysis, to avoid fouling analyzers with liquid input, and to maintainproper system operation, it is important to maintain a vaporized liquidsample at temperatures and pressures which are safe for analysis andwhich minimize phase transition and the risk of vapor condensation.

In an effort to address such issues, equipment has been developed toprovide staged/stepped pressure reduction that maintains selecttemperatures to minimize the risk of approaching the vapor's phasetransition boundary. For example, staged de-pressurizing regulatorsystems achieve multistage-pressurization reduction while maintainingsufficient temperatures to prevent vapor phase transition migration.Such systems are typically located in-line between the output of aliquid sample vaporizer and vapor feed line to a downstreamanalyzer/chromatograph. But as prior art regulators are not dynamicallyadjustable, they require specified minimum output pressures to meet orexceed the threshold input vapor gating pressure of the immediatedownstream system. Furthermore, an array of dedicated in-line regulatorsare typically manufactured and calibrated for a specific applicationand, once manufactured, are not easily converted or adaptable for usesoutside the specific parameters of the application.

Other pressure regulating designs seek to reduce the footprint of anarray of discrete individual systems by stacking the pressure reducingregulator elements in a modular, multistage structure. While achieving asmaller footprint, such regulator systems or arrays suffer from sharedfunctional deficiencies of multi-unit systems such as the inability ofdynamic adjustment and calibration of the pressure parameters forindividual modules. In this type of prior at system, the range ofparameters for each unit/module is pre-set and features factorypre-calibration of input pressure and output pressure where the outputpressure level must exceed the required minimum input pressure forintroduction into the downstream module to assure operation of theentire regulating system. In operation, the exit pressure from theimmediate upstream module may fall below the minimum threshold pressurerequired to gate the vapor to the adjacent downstream stage. Thus, thearray fails to deliver the requisite vapor sample to the downstreamanalyzer or collection vessel.

By way of example, in the case of a four-stage modular regulator, theminimum supply pressure input to the first stage in the series must besufficiently high so that following the third stage, the degree ofdepressurization still exceeds the minimum threshold for introductioninto the fourth stage. If that threshold is not met, the prior artsystems will cease to pass the vapor to the downstream elements.

The opposite problem may arise with prior art system operations. In acase of over-pressurized sample sources, the vapor pressure of theeventual output may exceed the permissible pressure threshold of adownstream analyzer. In such a case there is no protection againstdelivery of damaging over-pressurized gas to the chromatograph. In otherwords, the pre-set pressure, of for example, the fourth stage input istoo high for the required pressure reduction of the output for safeoperation of the analyzer.

There exists, therefore, a need for improvement to the presentlyaccepted and commonly used devices and methods of sampling andcontrolling pressure regulation of extracted vapor samples.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a device, system and methodthat do not suffer from at least the problems described previouslyherein and which can provide a more efficient, dynamic and reliablepressure regulating device for regulating the pressure of a vapor gassample which can then be passed to an gas analyzer or otherpressure-sensitive equipment.

Another object of an aspect of the invention is to provide a compactadjustably calibratable multi-stage pressure regulating device, systemand method that represent an improvement over the prior art.

Yet a further object of an aspect of the invention is to provide astaged system and method for significant pressure reduction of a vaporgas sample avoiding dew point dropout/condensation.

Still a further object of the invention is to provide an integrated,multistage depressurizing regulator that maintains the pressure andtemperature of a vapor gas sample well outside the two-phase envelopeboundary.

It is a further object of the invention to provide a device, system andmethod that can be used to deliver more accurate measurement of BTUvalues used for custody transfer. Further, to monitor and reduceundesired presence of sour gas samples, the device, system and methodcan also be used to deliver accurate measurement of trace contaminantssuch as, mercury (Hg), hydrogen sulfide (H₂S), carbonyl sulfide (COS),mercaptans (RSH) and aromatics such as BTEX (Benzene, Toluene,Ethylbenzene and Xylene).

It is yet another object of the invention to provide a device that ismore compact, less susceptible to mechanical failure, and provides fordynamic pressure calibration adjustment.

Another object of the invention is to provide an automatic and/ormanually configurable compact device that maintains the integrity of thevapor composition from a vaporizer to an analyzer by avoidingintermittent condensation during multistage depressurizing ofmulti-component vapor gas.

Still another object of an embodiment of this invention is to provide acompact, generally unitary, multi-stage pressure regulation device withadjustable calibration of pressure inputs and outputs at individualstages.

Illustrative, non-limiting embodiments of the present invention mayovercome the aforementioned and other disadvantages associated withrelated art liquid gas vaporization and measurement systems. Also, thepresent invention is not necessarily required to overcome thedisadvantages described above and an illustrative non-limitingembodiment of the present invention may not overcome any of the problemsdescribed above.

To achieve the above and other objects an embodiment in accordance withthe invention A pressure regulating system, for stepped depressurizationof a vapor sample, featuring a housing; a core disposed generallylongitudinally along a central axis of the housing; a vapor sample inputport connected to a vapor sample passage integrally formed within thehousing; a plurality of unvented openings on an upper surface of thehousing, each unvented opening being peripherally disposed about thecore and adjacent to at least one other unvented opening, each of theunvented openings having a select cross-sectional dimension andextending substantially in the direction of elongation of the housing,and each of said unvented openings being connected by an interconnectchannel integrally formed in said housing and connected to an adjacentventless opening; a plurality of pressure regulating valves each of saidplurality of pressure regulating valves having a cross-sectionaldimension corresponding to the select cross-sectional dimension of anunvented opening, each of said plurality of pressure regulating valvesbeing switchable between a non-pressure regulating mode and a pressureregulating mode for passing a vapor sample to an adjacent downstreampressure regulating valve at a select regulated pressure via theconnected interconnect channel where each of said plurality of pressureregulating valves establishes a pressure reducing stage and includes avalve stem, a sense piston, and sense piston actuator; and a reducedvapor sample output port.

A further embodiment of the invention includes a pressure regulatingsystem for depressurization of a natural gas vapor sample, incorporatinga regulator body with a first surface and a second opposite surface anda perimetric surface incorporating a vapor sample input port and a vaporsample output port, a thermal control means for maintaining thermalstability of the regulator body; a plurality of unvented openingsdisposed about the first surface proximate to the perimetric surface,each of the plurality of unvented openings having a selectcross-sectional dimension and extending between the first and secondsurfaces, and each of said unvented openings being connected by aventless interconnect channel integrally formed in said housing andconnected to an adjacent unvented opening; and adjustable valve assemblymeans for adjustable pressure regulation dimensioned to be containedwithin each of the unvented openings to regulate vapor pressure of thevapor sample to a preset maximum and preventing passage of a vaporsample at a pressure outside of a preset range to pass to an adjacentvalve assembly means through the ventless interconnect channel toestablish a means for serial, staged depressurization of the vaporsample while maintaining the vapor sample in the vapor phase

Another embodiment of the invention includes a pressure regulatingdevice including a housing having a core disposed generallylongitudinally along a central axis of the housing, a vapor sample inputport connected to a vapor sample passage integrally formed within thehousing, and a plurality of openings on an upper surface, each openingbeing radially disposed around the core and extending substantially inthe direction of elongation of the housing. The pressure regulatingdevice also includes a plurality of pressure regulating valvesconfigured to reduce the pressure of a vapor sample received from thevapor sample passage, each pressure regulating valve being disposedwithin a respective opening to create a vapor sample flow path therein,and an assembly having a base and substantially central stem orthogonalto the base and extending axially therefrom, the stem being disposedwithin the core. In one example, the pressure regulating device includesan assembly having a base and stem orthogonal to the base and extendingaxially therefrom, the stem being formed so as to generally conform tothe dimensions of the core.

A further embodiment of the invention includes a method for reducing thepressure of a vapor sample through a plurality of calibrated steppedstages of pressure reduction, the method comprising the steps of:inputting the vapor sample via a vapor sample inlet port formed within ahousing of a pressure regulating device; selectively directing the vaporsample to an adjustable first pressure regulating valve assemblydisposed within a first ventless opening integrally formed in thehousing where the first ventless opening is connected by an interconnectchannel to an adjacent second pressure regulating valve assemblydisposed within a second ventless opening integrally formed in thehousing; reducing the pressure of the vapor sample to a preset amountand passing the vapor sample to the adjacent adjustable second pressureregulating valve assembly disposed within the second ventless openingintegrally formed in the housing where the second ventless opening isconnected by an interconnect channel to an adjacent third pressureregulating valve assembly disposed within a third ventless openingintegrally formed in the housing; reducing the pressure of the vaporsample to a second preset amount and passing the vapor sample to anadjacent adjustable third pressure regulating valve assembly; andmaintaining the sample in the vapor phase as the vapor sample passesthrough the first, second and third regulating valve assemblies.

BRIEF DESCRIPTION OF THE DRAWINGS

The aspects of the present invention will become more readily apparentby describing in detail illustrative, non-limiting embodiments thereofwith reference to the accompanying drawings, in which:

FIG. 1A is a perspective view illustrating a pressure regulating devicein accordance with an embodiment of the present invention.

FIG. 1B is a perspective cut-away view of the pressure regulating devicein accordance with an embodiment of the invention.

FIG. 1C is an expanded view of a pressure regulating valve of thepressure regulating device of FIG. 1B in accordance with an embodimentof the invention illustrating vapor flow through the valve.

FIG. 1D is a top view of the pressure regulating device in accordancewith an embodiment of the present invention.

FIG. 1E is a cross-sectional view of the pressure regulating device ofFIG. 1D in accordance with an embodiment of the invention.

FIG. 2A illustrates a flow path within different stages of the pressureregulating device in accordance with an embodiment of the invention.

FIG. 2B illustrates a flow path within different stages of the pressureregulating device in accordance with an embodiment of the invention.

FIG. 2C illustrates a flow path within different stages of the pressureregulating device in accordance with an embodiment of the invention.

FIG. 3A is perspective view of the interior of the pressure regulatingdevice in accordance with an embodiment of the invention.

FIG. 3B is perspective view of the interior of the pressure regulatingdevice in accordance with the embodiment of the invention illustrated inFIG. 3A.

FIG. 4 is an exploded view of a pressure regulating system andcomponents in accordance with an embodiment of the invention.

FIG. 5A is a cross-sectional view of an embodiment of the inventionproviding for regulating high-pressure.

FIG. 5B is an exploded view of an embodiment of a high-pressureregulating valve assembly.

DEFINITIONS

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms, “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the root terms “include”and/or “have”, when used in this specification, specify the presence ofstated features, integers, steps, operations, elements, and/orcomponents, but do not preclude the presence or addition of at least oneother feature, integer, step, operation, element, component, and/orgroups thereof.

It will be appreciated that as used herein, the terms “comprises,”“comprising,” “includes,” “including,” “has,” “having” or any othervariation thereof, are intended to cover a non-exclusive inclusion. Forexample, a process, method, article, or apparatus that comprises a listof features is not necessarily limited only to those features but mayinclude other features not expressly listed or inherent to such process,method, article, or apparatus.

As used herein “connected” includes physical, whether direct orindirect, permanently affixed or adjustably mounted. Thus, unlessspecified, “connected” is intended to embrace any operationallyfunctional connection.

In the detailed description, references to “one embodiment”, “anembodiment”, or “in embodiments” mean that the feature being referred tois included in at least one embodiment of the invention. Moreover,separate references to “one embodiment”, “an embodiment”, or “inembodiments” do not necessarily refer to the same embodiment; however,neither are such embodiments mutually exclusive, unless so stated, andexcept as will be readily apparent to those skilled in the art. Thus,the invention can include any variety of combinations and/orintegrations of the embodiments described herein.

As used herein “substantially”, “relatively”, “generally”, “about”, and“approximately” are relative modifiers intended to indicate permissiblevariation from the characteristic so modified. They are not intended tobe limited to the absolute value or characteristic which it modifies butrather approaching or approximating such a physical or functionalcharacteristic.

As used herein “tubular” means any axially-oriented generally elongated,generally symmetrical geometric configuration and is not limited to astructure possessing just a cylindrical cross-sectional profile.

As used herein, if not specified, “gas” means any type of gaseouschemical matter or fluid in gas form including, for example, a specificvaporized hydrocarbon component containing liquid matter, and/or aheterogenous mixture of hydrocarbon components, where gas may includenatural gas liquids, and liquified natural gas, gas mixtures thereof,and equivalents.

Exemplary, non-limiting, embodiments of the present invention arediscussed in detail below. While specific configurations and dimensionsare discussed to provide a clear understanding, it should be understoodthat the disclosed dimensions and configurations are provided forillustration purposes only. A person skilled in the relevant art willrecognize that, unless otherwise specified, other dimensions andconfigurations may be used without departing from the spirit and scopeof the invention.

It will also be appreciated that as used herein, any reference to arange of values is intended to encompass every value within that range,including the endpoints of said ranges, unless expressly stated to thecontrary.

DETAILED DESCRIPTION

In the following description, reference is made to the accompanyingdrawings which are provided for illustration purposes as representativeof specific exemplary embodiments in which the invention may bepracticed. The following illustrated embodiments are described insufficient detail to enable those skilled in the art to practice theinvention. It is to be understood that other embodiments may be utilizedand that structural changes based on presently known structural and/orfunctional equivalents may be made without departing from the scope ofthe invention.

Given the following detailed description, it should become apparent tothe person having ordinary skill in the art that the invention hereinprovides a novel pressure regulating device and a method thereof forproviding significantly augmented efficiencies while mitigating problemsrecognized and unrecognized of the prior art structures and methods.

FIGS. 1A-1E illustrate various views of the different parts tubularupper body or housing 102, which in the illustrated embodiment possessesan elongated cylindrical geometry, a lower body or assembly 116 with acorresponding geometry, and adjustable pressure regulating valves 112 ofa pressure regulating system which when assembled, provides for apressure regulating device 100 in accordance with an embodiment of theinvention. The invention is not limited to a cylindrical/circularcross-sectional geometry as other geometries such as polygonal, oval,etc. are equally employable.

In overview, the pressure regulating device 100 includes the assembly116 which preferably is formed of a corrosion-resistant super alloy,such as stainless-steel or aluminum. In lieu of alloys, the upper body102 and assembly 116 may also be fabricated/molded of high-strengthengineered thermoplastics, ceramics, or other materials compatible foruse in connection with vapor gas pressure regulation. The assembly 116of the current embodiment includes a base 116A featuring a circularcross-section, an upper surface defining a shoulder, a stepped, andpartially hollowed stem 116B projecting centrally and orthogonally fromthe shoulder. The stem 116B dimensionally conforms to and is adapted forinsertion into a complementary stepped axial core or bore 111 in thebody 102 comprising larger diameter, lower segment 111C tapering tonarrower bore middle segment 111B and expanding to upper bore segment111A.

The stem 116B includes an inner cavity 136 for receiving and retainingan optional electrical heating cartridge element 138 powered by feedlines 134 and the output sensed by a thermocouple 135 both projectingfrom a base of the heating cartridge element 138 and exiting theassembly 116 via electrical and control output port 129.

In the illustrated embodiment, the upper body 102 features an opening107 formed in the upper surface 106 at the top of the bore 111. A seriesof threaded plugs 114 are disposed about and near the perimetric annulus104 of the upper surface 106. Each of the plugs 114 seals an accesschannel 115 that angles radially inwardly from perimetric annulus 104toward the bore 111. The upper surface 106 also features fiveaxially-offset, longitudinally projecting, valve receiving recessedopenings 146. The recessed openings 146 are disposed around the opening107 and extend longitudinally and generally parallel to the axis ofelongation of the upper body 102. Each of the recessed openings 146 isstepped and dimensioned to seat and retain a pressure regulating valve112 (see FIG. 4).

FIG. 1B illustrates a cut-away perspective view of the pressureregulating device 100 in which the assembly 116 is arranged within thesegments 111A, B, C of the upper body 102 and pressure regulating valves112 are seated in the respective openings 146. As illustrated in thecutaway FIG. 1B, a first pressure regulating valve 112 is configured toreceive the vapor sample from the vapor sample inlet port 108 via theradially-oriented vapor sample passageway 109.

A vapor gas sample is directed to a first-stage pressure regulatingvalve 112 via a vapor sample passageway 109 at connector port 113A. Asdetailed below, the pressure regulating valve 112 reduces the pressureof the vapor gas sample which is then directed in serial fashion to anadjacent pressure regulating valve 112 for additional pressure reductionwhile being optionally simultaneously thermally controlled via theoptional central heating cartridge element 138. Upon exiting afinal-stage pressure regulating valve 112, the vapor gas sample, nowbeing at an analyzer safe pressure, is directed from the tubular upperbody 102 through vapor sample passageway 142 to vapor sample outlet port110.

Referring to the structure and placement of the lower portion of thepressure regulating valve 112 it is seated in the valve receivingrecessed opening 146 to permit controlled axial adjustment based onspring pressure. The recessed opening 146 includes in steppedconfiguration, a lower bore 118, a diametrically larger middle bore 121,and a larger upper bore 123, within opening 146 from upper planarsurface 106. The pressure regulating valve 112 features in combination,an upwardly biased, axially disposed helical compression valve stemspring 112M, a valve stem 112L segmented into a cylindrical valve stembase 112L-1 terminating with an upper shoulder defining a flared,conical valve stem projection 112L-2, a valve stem tip 112L-3 thatprojects upwardly through a valve seat 112J and a valve guide 112I tosense piston 112G and a downwardly biased flat/Belleville/wave sensepiston actuator spring 112 F. The upper shoulder acts as a stop for theupwardly biased, axially disposed helical compression valve stem spring112M that engirds the valve stem 112L below the conical valve stemprojection 112L-2. An elongated segment of the valve stem tip 112L-3projects axially and upwardly from the tapering surface of the conicalvalve stem projection 112L-2 to the bottom surface of the sense piston112G.

Disposed within the middle bore 121 is a valve seat 112J and valve guide112I sealed to each other with a sealing device 112K, such as an 0-ring,and each having a substantially central channel 127 therein allowing forpassage of the valve stem tip 112L-3 and vapor gas sample therethrough.The valve guide 112I can be connected to the tubular upper body 102 bybeing bolted or screwed into the tubular upper body 102 via guide hole131. The valve seat 112J faces the lower bore 118 on one surface and thevalve guide 112I on the other, both of which form an entirety of themiddle bore 121. The valve seat 112J can be composed of a compliantmaterial, such as a ceramic, an elastomer or silicone, which helpsprevent contamination or sealing of the substantially central channel127 by the conical valve stem projection 112L-2. The conical valve stemprojection 112L-2 also protects against contamination due to its shapeas it compresses into the valve seat 112J and acts as a wiper.Accordingly, the central channel 127 through the valve seat 112J has alarger diameter than the central channel 127 through the valve guide112I to allow for the compression and secure wiping contact with thevalve seat 112J by the conical valve stem projection 112L-2. The valveseat 112J and valve guide 112I are fixed in position within the middlebore 121 and do not move during the operation of the pressure regulatingvalve 112.

The upper bore 123 includes an axially disposed sense piston actuator112F, such as for example a spring, engirded by a spring housing 112Cand extending from an adjustment device 112A, such as a screw or bolt,protruding from opening 146 to a sense piston 112G disposed within alower portion of the upper bore 123. A pressure regulating valve 112 canbe in one of three positions at any given time: a fully open position, aregulating position and a fully closed position. A pressure regulatingvalve 112 will be in a fully open position when the pressure regulatingdevice 100 is not in use and no pressure or very low pressure is presentwithin the lower bore 118. Thus, this condition exists when a pressureexerted by the sense piston spring 112F far exceeds the pressure of anyminimal incoming vapor gas sample traveling into the lower bore 118 suchthat there is very little to no axial movement imposed upon the valvestem 112L via a valve stem spring 112M. This provides a sizable gapbetween the conical valve stem projection 112L-2 and the valve seat112J.

When the pressure regulating device 100 is in use and regulating anincoming vapor gas sample the pressure regulating valve(s) 112 will bein the regulating position. For this condition to exist, a pressureexerted by the sense piston spring 112F on sense piston 112G based onthe setting of the sense piston spring 112F offsets the pressure of anyincoming vapor gas sample traveling into the lower bore 118. Thus, whenthe pressure regulating valve(s) 112 are in the regulating position andthe pressure exerted by the sense piston spring 112F exceeds thepressure of any incoming vapor sample traveling into the lower bore 118,the sense piston 112G will be approximate but not contacting the topsurface of the valve guide 112I and exerting a linear downward pressureon the valve stem tip 112L-3 which displaces conical valve stemprojection 112L-2 from the valve seat 112J. This linear displacementmaintains the flow of any vapor sample from the lower bore 118 to theupper bore 123 via a channel 127. However, an incoming vapor gas samplehaving a pressure larger than the pressure exerted by the sense pistonspring 112F will force the valve stem 112L to move axially upwardthereby causing the valve stem tip 112L-3 to slightly displace the sensepiston 112G from its position approximate the valve guide 112I whilealso displacing the conical valve stem projection 112L-2 axially upwardinto a portion of the channel 127 within valve seat 112J. Thus, when inoperation and in the regulating position, the pressure regulatingvalve(s) 112 will continually adjust based on pressure settings at eachstage and incoming vapor sample pressure until a steady state isattained in which pressure is reduced at each stage for consumption at aconstant flow rate for a downstream analyzer.

FIG. 1C illustrates an expanded view of the pressure regulating valve112 in the regulating position. As illustrated, a vapor gas sample 119having a pressure greater than that of the pressure exerted upon thevalve stem tip 112L-3 by sense piston 112G has entered the lower bore118 thereby causing the valve stem 112L to move axially upward such thatthe valve stem tip 112L-3 slightly displaces the sense piston 112Gaxially upwards within the upper bore 123 and causes the conical valvestem projection 112L-2 to encroach the portion of the channel 127 withinvalve seat 112J. As illustrated, the central channel 127 formed betweenthe valve seat 112J and the valve guide 112I has a slightly largerdiameter than that of the valve stem tip 112L-3 which allows for theflow of the vapor sample 119 from the lower bore 118, through the middlebore 121 and into a gap 128 within the upper bore 123. Accordingly, anyvapor sample 119 entering the upper bore 123 will have its pressurereduced based on the pressure differential between the lower bore 118and the upper bore 123, the passage within the limited space of thecentral channel 127 and the limited passage size between the valve seat112J and the conical valve stem projection 112L-2. The pressure-reducedvapor sample 119 will continue to pass through the bores 118, 121 and123 while the pressure exerted by the vapor sample 119 on the sensepiston 112G is the same as the valve setting of the sense piston spring112F. If the pressure of the vapor sample 119 is no longer great enoughto match the force exerted by the sense piston spring 112F, the pressureregulating valve 112 will move to a more open position where sensepiston spring 112F will displace the sense piston 112G which in turndisplaces the conical stem projection 112L-2 away from valve seat 112Jvia valve stem tip 112L-3. Conversely, if the pressure of the vaporsample flow 119 is too high, conical valve stem projection 112L-2 blocksthe valve seat 112J thereby preventing vapor flow.

Accordingly, any vapor sample 119 that exits the lower bore 118 to gap128 in the upper bore 123 while the pressure regulating valve 112 was inthe regulating position will exit at a preselected pressure viainterconnect channel 144 and be directed to a next-stage pressureregulating valve 112 in the body 102 for further pressure reduction.This construct and operation eliminate the need for over-pressure vaporgas venting from the interconnection channel 144 between the pressureregulating valves. Provision of an for over-pressurized vapor output toa downstream regulating valve assembly 112 is both unnecessary andundesirable because the outputted vapor pressure in the interconnectionchannel 144 has already been reduced to an adjusted level. Consequently,the unvented, less complicated structure of the disclosed embodiment isachieved. Also venting vapor before analysis compromises the integrityand precision of the ultimate sample analysis.

The pressure regulating valve 112 will be in a fully closed positionwhen the output of the valve is blocked, the outlet pressure conditionis satisfied and no volumetric consumption or condensation is present(i.e. the downstream analyzer is off and not continuously reducingpressure at the outlet 110.) In other words, pressure formed by theincoming vapor sample that gets blocked will translate backward andexert a large pressure on the sense piston 112G in addition to anypressure exerted on the sense piston spring 112G by the valve stem tip112L-3. This increase in pressure on the sense piston 112G axiallydisplaces the sense piston 112G upward within the upper bore 123 therebyallowing the valve stem 112L to correspondingly axially displace upwardand be fully seated within the valve seat 112J thereby fully blockingthe channel 127.

FIGS. 2A-2C illustrate the flow of the vapor sample 119 as it flows fromthe vapor sample passageway 109 downstream through five stages to thevapor sample outlet port 110 via the plurality of pressure regulatingvalves 112 and corresponding interconnect channels 144. In this example,it is assumed that the pressure regulating valves 112 have been properlycalibrated and have had appropriate pressure settings applied via theadjustment device 112A such that the incoming vapor sample 119 will haveenough pressure at each pressure regulating valve 112 to force eachpressure regulating valve 112 into the regulating position. Theadjustment device 112A is configured to move axially within the opening146 via a threaded spring housing 112C and termination nut 112B suchthat it displaces a washer 112E abutting the sense piston spring 112F(See FIG. 4). Alternatively, as illustrated in FIGS. 1E and 3,adjustment devices 112A, such as screws or bolts, can be configured todirectly abut the upper planar surface 106 of the tubular upper body 102and be threaded therethrough into the pressure regulating valves 112 toadjust pressure settings. In this example, the adjustment devices 112Arequire less space thereby reducing the overall profile of the pressureregulating device 100. However, unlike the adjustment device 112Aconfiguration illustrated in FIGS. 1A, 1B, 2 and 3, this requiresadditional threading within the bore 125 of the pressure regulatingvalves which can increase manufacturing cost.

To adjust the pressure of a particular stage of the pressure regulatingdevice 100, the adjustment device 112A can be rotated through thethreaded spring housing 112C to either compress or decompress the sensepiston spring 112F via washer 112E thereby and calibrate by increasingor decreasing the pressure of the sense piston spring 112F on theabutting sense piston 112G. The higher the pressure setting at aparticular stage translates to a higher sense piston spring 112Fpressure which forces the sense piston 112G to displace the conicalvalve stem projection 112-L2 to a less restrictive position approximatevalve seat 112J via the valve stem tip 112L-3. Accordingly, in FIGS. 2Aand 2B, the pressure setting of the pressure regulating valve 112 atStage 1 will be greater than the pressure setting of the pressureregulating valve 112 at Stage 2 and so forth with the pressure settingof the pressure regulating valve 112 at Stage 5 being the lowest.

Referring to FIGS. 1D and 1E, the pressure setting at each stage can beset and verified via respective access channels 115 each connected to acorresponding interconnect channel 144 at the output of a correspondingpressure regulating valve 112. For example, to calibrate the pressuresetting of the pressure regulating valve 112 at Stage 5, the pressurewithin the interconnect channel 144 output from the pressure regulatingvalve 112 of Stage 5 towards passageway 142 is measured viacorresponding access channel 115. FIG. 1E illustrates an access channel115 connected to the interconnect channel 144 of the pressure regulatingvalve 112 at Stage 1. The access channel 115 is illustrated as beingplugged by the access channel hole plug 114, such as a crown cap orscrew cap. However, to calibrate the pressure and/or temperature atStage 1, the access channel hole plug 114 is removed and either or bothof a pressure sensor and a thermal sensing device can be installed inaccess port 114 to provide serve as additional input to the controller.Accordingly, when the vapor sample 119 is being passed through thepressure regulating device 100, the pressure and/or temperature sensorwill detect the pressure/temperature of the vapor sample 119 exiting thepressure regulating valve 112 at Stage 1 in the interconnect channel 144via access channel 115. The pressure regulating valve 112 can then beadjusted via adjustment device 112A until the pressure sensor detects adesired pressure reduction reading from the vapor sample 119 input intothe vapor sample input port 108. This process can then be repeated foreach successive pressure regulating valve 112 at each stage using apressure sensor at a corresponding access channel 115. Correspondingly,the thermal heater can be adjusted to raise or lower the vapor sampletemperature as called for and manipulated by the controller.

Another method for calibrating the pressure regulating device 100 is tomeasure the pressure at each access channel 115 at the same time andsimultaneously adjust the pressure regulating valve 112 at each stage.The pressure settings can be adjusted based on a specific application orparticular gas profile. Of course, when calibration is not beingperformed or when calibration is completed, the access channel holeplugs 114 will be replaced to plug the access channels 115, unless it isdesired to maintain automated pressure sensors continuously.

The ability to individually adjust the pressure setting of pressureregulating valves 112 at different stages provides for a pressureregulating device 100 that can be used for a variety of gases havingdifferent profiles. Therefore, based on the thermodynamic properties andphase curve of a particular vapor gas profile being processed by thepressure regulating device 100, each pressure regulating valve 112 canbe calibrated to reduce pressure at each stage at reduction levels thatdo not allow for reversion or reentry of the vapor gas sample into thetwo-phase region of the phase curve. The reduction at each stage can befurther controlled by the assembly 116 and, more particularly, theoptional heating cartridge element 138, substantially centrally locatedwithin the radially surrounding pressure regulating valves 112 whichconsistently maintains the temperature of the vapor sample 119 duringall depressurizing stages required to prevent dew pointcondensation/hydrocarbon dew point dropout. Accordingly, the pressureregulating device 100 can be dynamically calibrated over time forvarious applications and/or gas profiles rather than requiring adifferent pressure regulating device for each application or gasprofile. Further, the pressure regulating device 100 does not require aspecifically high minimum amount of initial pressure entering the firststage as the other stages can be dynamically set lower to offset anyinitially low pressure entering the pressure regulating device 100.

Referring again to FIGS. 2A and 2B and as one example, once the pressureregulating valves 112 are properly calibrated using correspondingadjustment devices 112A and access channels 115, the vapor sample 119input into the lower bore 118 via passageway 109 at connector port 113Awill have a pressure P₀ greater than the pressure setting at Stage 1which will cause the valve stem tip 112L-3 to shift axially upward todisplace the sense piston 112G. This displacement causes the conicalvalve stem projection 112L-2 to displace axially upwards within thevalve seat 112J thereby restricting the flow of the vapor sample 119directed through channel 127 within middle bore 121 and upper bore 123to a reduced pressure P₁ which is subsequently directed to Stage 2 viainterconnect channel 144. The vapor sample 119 having reduced pressureP₁ then enters the lower bore 118 of pressure regulating valve 112 atStage 2 which has a pressure setting lower than P₁ such that the vaporsample 119 can again pass through the pressure regulating valve 112 tothe next stage. This process repeats until the vapor sample 119 having areduced pressure P₅ exits the pressure regulating valve 112 at Stage 5via outlet sample port 110 to be passed to external equipment such as ananalyzer. As the vapor sample 119 is flowing through each stage atrespective radially disposed pressure regulating valves 112, the vaporsample 119 is can be optionally thermally controlled via the optionalheating element 138 disposed substantially centrally within the stem116B of the assembly 116. Accordingly, the pressure of the vapor sample119 is subject to thermal control as well as a controlled pressurereduction at each stage to avoid dew point dropout into a two-phasesample during the depressurization sequence. When the well integratespressure and temperature sensing between each stage, the vapor ismaintained as a condition outside the phase curve to avoid jeopardizingthe sample by creating a two phase separation condition. The controlledenvironment provided by the specifically calibrated pressure regulatingvalves 112 and the substantially centrally located heating element 138maintain the vapor sample 119 in the vapor phase region therebyeliminating the risk of condensation or dew point dropout which couldtaint analysis of the sample and/or damage or destroy a downstream theanalyzer.

Although not illustrated, it is further contemplated herein that thepressure regulating device 100 could be automatically calibrated with amulti-faceted calibration tool either manually or with a motor which ismechanically connected to the adjustment devices 112A and electricallyconnected to or including a pressure sensor(s). Such a calibration toolcould compute pressures detected via the pressure sensor(s) and use themotor to automatically adjust one or more adjustment devices 112A inreal-time accordingly to provide an optimal calibration setting of eachstage. Alternatively, the pressure regulating device 100 could include amotor connected to the adjustment devices 112A which could be accessedlocally or remotely to adjust the pressure settings at each stage basedon readings processed from one or more pressure sensors connected to oneor more access channels 115.

FIGS. 3A and 3B illustrate an interior view of the assembled pressureregulating device 100 in accordance with an embodiment of the invention.As illustrated, the pressure regulating device 100 includes theplurality of access channels 115 connected to interconnect channels 144thereby providing the ability to measure pressure and calibrate thevarious stages. Also illustrated is the substantially central locationof the heating cartridge element 138 (disposed in the assembly stem116B) within the radially disposed pressure regulating valves 112. Avapor gas sample enters the pressure regulating device via vapor sampleinput port 108 and is directed to the pressure regulating valve 112 ofStage 1 via passageway 109. Assuming the pressure regulating device isproperly calibrated, the vapor sample will be directed in series througheach pressure regulating valve 112 causing a pressure reduction at eachstage such that the vapor sample exiting the pressure regulating valve112 of Stage 5 via outlet 110 will have a pressure suitable for analysisby pressure-sensitive equipment such as a chromatograph.

FIG. 4 illustrates an exploded view of an exemplary pressure regulatingsystem 101 which when assembled forms the pressure regulating device100. The pressure regulating system 101 includes one or more pressureregulating valves 112, the tubular upper body 102, assembly 116 andheating element 138. One or more of the pressure regulating valves 112include the adjustment device 112A threaded through the termination nut112B, spring housing 112C and housing seal 112D to contact washer 112Ewhich can increase or decreases the force exerted by sense piston spring112F against sense piston 112G. The valve stem 112L, enclosed withinvalve stem spring 112M, provides an opposing force towards the sensepiston seat 112G via movement through a valve seat 112J and valve guide112I sealed via a guide seal 112K. The one or more pressure regulatingvalves 112 are fitted within the one or more openings 146 which extendaxially within the tubular upper body 102 to provide a step-bored wellwithin an interior of the tubular upper body 102.

In one example, the segment 111B is formed within the tubular upper body102 by boring from the bottom portion of the body 102 near the radiallybored vapor sample input 108 and output ports 110 (See FIG. 1B). Thesegment 111B is formed to be tapered roughly at its midpoint along anaxial length of the segment 111B. The opening 107 can be separatelydrilled from the upper planar surface 106 of the tubular upper body 102to form and connect the segment 111A with the bored segment 111B. Theopening 107 in this example is formed from the upper planar surface 106because the diameter of the segment 111A is larger than the diameter ofthe segment 111B formed directly below the opening 107. It is at thispoint at which the segment 111A meets the segment 111B that an assemblyseal is used to seal the assembly 116 within the tubular upper body 102when inserted therein. This ensures maximum heat transfer by maintainingthe heating cartridge element 138 within the central interior of thetubular upper body 102 and by maintaining stem 116B against the taperformed by segment 111B.

The assembly 116 includes the inner cavity 136 bored within the assemblystem 116B from the base 116A of the assembly 116 to provide forinsertion of the optional heating cartridge element 138 therein. Thecavity may be cylindrical or tapered to increase the contact area andenhance thermal energy transfer into body 102. The electrical feed lines134 and thermocouple 135 can be inserted via control output port 129radially bored into the assembly 116 and connected to the heatingcartridge element 138 via the inner cavity 136. The thermocouple 135 canbe connected to a proportional-integral-derivative (PID) controllerand/or Programmable Logic Controller (PLC) (not shown), such as an AllenBradley 850 series PLC or equivalent controller, to provide signalfeedback and control of the pressure regulating device 100. Once theheating cartridge element 138, electrical feed lines 134 andthermocouple 135 are enclosed within the assembly 116, the opening boredinto the base 116A of the assembly 116 is closed with an internallythreaded plug to provide a closed system. For safety, the plug can beexplosion-proof in accordance with one or more applicable standards,such as the ATEX standard.

The assembled pressure regulating device 100 provides for a compactdesign that is less costly to manufacture and enables use of thepressure regulating device 100 in smaller areas within sampleconditioning equipment. As discussed herein, the pressure regulatingdevice 100 can be used for a variety of different applications as it canbe dynamically adjusted based on a specific application or profile ofgas to be measured. Further, the radially located pressure regulationvalves 112 connected in series avoid issues created by gravity commonlyassociated with vertically designed multi-stage regulators.

FIG. 5A depicts an alternative embodiment for the regulating valveassembly. This embodiment provides for a greater degree ofdepressurizing the incoming vapor sample for samples at higher startingpressures for example, upwards from 41300 kPa (6000 psi) to 69000 kPa(10.000 psi). The high pressure regulator embodiment includes aregulator housing 102 and a base 116 that remain essentially unchangedfrom the above-described embodiments. The third through fifth regulatingvalves 112, likewise remain unchanged from the foregoing. However, atleast the first and, preferably, the second pressure regulating valveassemblies 512 differ. The high-pressure embodiment features a nestedbifurcated sense piston 530 and at least one heavier sense pistonactuator spring.

One embodiment of a high-pressure valve assembly is depicted in FIG. 5B.The high pressure valve embodiment, as illustrated, dimensionallyconforms to the valve assemblies 112 but incorporates a two-componentsense piston 512G structure essentially establishing an inner corecylinder element 512Gi slidably nested in an outer shell cylinder 512Goto allow for relative axial movement between the two. The cylinderelements 512 Gi and 512Go may include one or more sealing rings 532disposed about their exterior surface to prevent vapor leakage. The highpressure depressurizing arrangement also eliminates the washer 112Edisposed below the sense piston depicted in FIG. 4. Eliminating thewasher 112 enables use of a heavier downwardly biased sense pistonactuator spring or, preferably, as depicted in FIG. 5B, a dual springarrangement. The dual spring construct includes an inner spring 512Finested within an outer spring 512Fo which are both seated in the springhousing 512C. Disposed below, at least the inner spring is washer 530that has a diameter less than the inner diameter of the spring housing512C. In one embodiment, the inner spring 512Fi impinges directly on adisc-like washer 530 resulting in effectively enlarging the diameter ofthe inner center core cylinder 512Gi to concentrate the downward springforce from the inner spring 512Fi. This force translates through theinner core cylinder 512Gi and is transmitted to the valve stem tip512L-3. The outer spring 512Fo may impinge directly against the topsurface of the outer shell cylinder 512Go of the sense piston 512G.

In another embodiment, the diameter of the washer 530 extendssubstantially across the entire inner diameter of the spring housing512C resulting in direct contact with both the inner spring 512Fi andthe outer spring 512Fo. Where the diameter of the washer 530 correspondsto the outer diameter of the outer spring 512Fo, maximum spring force isapplied to the sense piston by both springs. Using a smaller diameterwasher reduces spring force pressure applied to the to the washer due tothe lessened contact with the springs. This feature permits a greaterdegree of design flexibility for achieving a desired depressurizingregulation.

In other words, this arrangement directs the entire compressive springforce of the springs 512Fi and 512Fo to the smaller diameter inner core512Gi through the washer 530 which enhances its effective compressionand the downwardly directed force on the upwardly projecting stem valve512L-3 where it contacts and presses against the inner core pistoncylinder 512Gi of the sense piston thereby providing effective pressureregulation at higher starting pressures.

Structurally, the washer 530 is formed from stainless steel or analternative rigid strong material, e.g., ceramic, non-reactive metalalloy, etc. and, preferably, includes a receiving notch centered incentral opening 532 dimensioned to receive and co-act with a protrusion534 projecting above the generally planar upper surface of the innercore piston cylinder 512Gi to positionally stabilize the washer 530 inthe spring housing 512C.

As noted, standardization of the housing bore sizes is achieved when thehigh pressure valve assembly dimensions correspond to theearlier-described valve assembly embodiments, However, wherecircumstances require, the bore sizes of the first two valve receivingrecessed openings may be enlarged to accommodate larger-sizedhigh-pressure regulating valve assemblies when necessary to achieve therequired degree of enhanced pressure regulation.

It would be understood for a person having ordinary skill in the artthat a device or method incorporating any of the additional oralternative details mentioned above would fall within the scope of thepresent invention as determined based upon the claims below and anyequivalents thereof. For example, although five access channels 115,five openings 146 and five corresponding pressure regulating valves 112are illustrated, it is contemplated herein that fewer or more of thesefeatures could be implemented to provide different configurations aswould be understood by one of ordinary skill in the art. Further, in anexemplary implementation discussed herein, the vapor gas sample isreceived from the output of a vaporizer device which has vaporized aliquid sample into vapor form. However, the pressure regulating device100 can be used to regulate a vapor gas sample received directly fromnatural gas or from other types of equipment at other points upstream ordownstream within a gas sample conditioning system.

Other aspects, objects and advantages of the present invention can beobtained from a study of the drawings, the disclosure and the appendedclaims.

What is claimed is:
 1. A pressure regulating system, for steppeddepressurization of a vapor sample, comprising: a housing; a coredisposed generally longitudinally along a central axis of the housing; avapor sample input port connected to a vapor sample passage integrallyformed within the housing; a plurality of unvented openings on an uppersurface of the housing, each unvented opening being peripherallydisposed about the core and adjacent to at least one other unventedopening, each of the unvented openings having a select cross-sectionaldimension and extending substantially in the direction of elongation ofthe housing, and each of said unvented openings being connected by aninterconnect channel integrally formed in said housing and connected toan adjacent ventless opening; a plurality of pressure regulating valveseach of said plurality of pressure regulating valves having across-sectional dimension corresponding to the select cross-sectionaldimension of an unvented opening, each of said plurality of pressureregulating valves being switchable between a non-pressure regulatingmode and a pressure regulating mode for passing a vapor sample to anadjacent downstream pressure regulating valve at a select regulatedpressure via the connected interconnect channel where each of saidplurality of pressure regulating valves establishes a pressure reducingstage and includes a valve stem, a sense piston, and sense pistonactuator; and a reduced vapor sample output port.
 2. The pressureregulating system of claim 1 where each pressure regulating valve ateach pressure reducing stage self-adjusts based on a select pressuresetting to regulate incoming vapor sample pressure.
 3. The pressureregulating system of claim 1, wherein at least one pressure regulatingvalve includes an adjustment device configured for adjustably setting anamount of pressure reduction applied at the pressure reducing stage bythe respective pressure regulating valve.
 4. The pressure regulatingsystem of claim 1, where in the pressure regulating mode the sensepiston at each stage is configured to be in an open, regulating positionand in the non-pressure regulating mode to be in a closed position basedon the disposition of the sense piston actuator and the valve stem. 5.The pressure regulating system of claim 4, wherein the disposition ofthe valve stem and sense piston actuator is based on a pressure of thevapor sample and a pressure reduction setting of the pressure regulatingvalve.
 6. The pressure regulating system of claim 3 where the unventedopenings are threaded and each adjustment device is threaded to moveaxially relative to the housing.
 7. The pressure regulating system ofclaim 5, when the sense piston is in the pressure regulating position,each pressure regulating valve has a valve stem channel for passing thevapor sample from the respective pressure regulating valve and when thesense piston is in the closed position the valve stem channel is blockedto prevent passage of the vapor sample through the pressure regulatingvalve.
 8. The pressure regulating system of claim 1, where the housingfurther comprises: an assembly having a base and stem generally disposedorthogonal to the base and extending axially therefrom, the stem beingformed so as to generally conform to the dimensions of the core andextending axially from a central portion of the base, and wherein thepressure regulating system further includes a heating device (138)disposed within the stem configured to heat vapor sample passing throughthe plurality of pressure regulating valves.
 9. The pressure regulatingsystem of claim 1, wherein the housing further includes a plurality ofunsealable pressure calibration ports disposed radially around theplurality of openings and each unsealable pressure calibration portcorresponding to a respective pressure regulating valve and beingconfigured to allow for measurement of pressure.
 10. The pressureregulating system of claim 9, wherein each of the unsealable pressurecalibration ports is connected with a respective interconnect channel.11. The pressure regulating system of claim 10, wherein at least one ofthe unsealable pressure calibration ports includes a pressure gaugeconfigured to display the pressure of the vapor sample the respectiveinterconnect channel.
 12. The pressure regulating system of claim 3where the adjustment device is electromechanically actuated and furtherincluding an unsealable pressure calibration port connected and anelectronic pressure sensor configured to provide an electronic signal tothe adjustment device for adjusting the pressure of the vapor samplepressure at a select pressure reducing stage.
 13. The pressure reducingsystem of claim 2 wherein at least one high pressure regulating valveassembly includes a pair of nested sense piston actuator compressionsprings, a bifurcated sense piston arrangement with an outer sensepiston and a nested inner piston axially slidable relative thereto, asense piston actuator contact disc disposed between the nested sensepiston actuator compression springs and the bifurcated sense piston saidcontact disk contacting the valve stem to concentrate the force of atleast one of the nested sense piston actuator compression springs toprovide enhanced pressure reduction.
 14. The pressure reducing system ofclaim 13 where the at least one high pressure regulating valve assemblypossesses dimensions corresponding to the other regulating valveassemblies.
 15. The pressure reducing system of claim 13 where thehousing includes five unvented openings where the first valve opening isconnected with the vapor sample passage connected to the vapor sampleinput port and where the first and second regulating valve assembliesare high pressure regulating valve assemblies.
 16. A method for reducingthe pressure of a vapor sample through a plurality of calibrated steppedstages of pressure reduction, the method comprising the steps of:inputting the vapor sample via a vapor sample inlet port formed within ahousing of a pressure regulating device; selectively directing the vaporsample to an adjustable first pressure regulating valve assemblydisposed within a first ventless opening integrally formed in thehousing where the first ventless opening is connected by an interconnectchannel to an adjacent second pressure regulating valve assemblydisposed within a second ventless opening integrally formed in thehousing; reducing the pressure of the vapor sample to a preset amountand passing the vapor sample to the adjacent adjustable second pressureregulating valve assembly disposed within the second ventless openingintegrally formed in the housing where the second ventless opening isconnected by an interconnect channel to an adjacent third pressureregulating valve assembly disposed within a third ventless openingintegrally formed in the housing; reducing the pressure of the vaporsample to a second preset amount and passing the vapor sample to anadjacent adjustable third pressure regulating valve assembly; andmaintaining the sample in the vapor phase as the vapor sample passesthrough the first, second and third regulating valve assemblies.
 17. Themethod for reducing the pressure of a vapor sample through a pluralityof stepped stages of pressure reduction of claim 16 further comprisingthe step of outputting the vapor sample to an analyzer for analysis. 18.The method for reducing the pressure of a vapor sample through aplurality of stepped stages of pressure reduction of claim 17 furthercomprising the step of adjusting the amount of pressure regulation byeach of the first, second, and third pressure regulating valveassemblies.
 19. A pressure regulating system for depressurization of anatural gas vapor sample, comprising: a regulator body with a firstsurface and a second opposite surface and a perimetric surfaceincorporating a vapor sample input port and a vapor sample output port,a thermal control means for maintaining thermal stability of theregulator body; a plurality of unvented openings disposed about thefirst surface proximate to the perimetric surface, each of the pluralityof unvented openings having a select cross-sectional dimension andextending between the first and second surfaces, and each of saidunvented openings being connected by a ventless interconnect channelintegrally formed in said housing and connected to an adjacent unventedopening; and adjustable valve assembly means for adjustable pressureregulation dimensioned to be contained within each of the unventedopenings to regulate vapor pressure of the vapor sample to a presetmaximum and preventing passage of a vapor sample at a pressure outsideof a preset range to pass to an adjacent valve assembly means throughthe ventless interconnect channel to establish a means for serial,staged depressurization of the vapor sample while maintaining the vaporsample in the vapor phase.
 20. The pressure regulating system fordepressurization of a natural gas vapor sample of claim 19 furthercomprising intelligent automatic control for each adjustable valveassembly means.